High on exercise

As the summer holidays go into full swing, a London-based scientist is advising people travelling on planes to stretch their legs every 15 minutes to avoid the risk of deep vein thrombosis (DVT).

According to Steve Hunter, an exercise scientist at London South Bank University, even sitting still for one hour can cause a decrease in blood velocity, which could lead to blood gathering in the lower legs, increasing the risk of DVT.

Mr Hunter's research shows that immobility when travelling by car or coach could cause similar problems. DVT - which could lead to a potentially fatal pulmonary embolism (when the blood clot travels from the leg and gets lodged into a blood vessel in the lungs, causing respiratory dysfunction) - is usually associated with long-haul flights because travellers are sitting in a confined space for long hours.

"I would advise everybody to think about exercising every 15 minutes, even if it's just pushing up to tip toes to work the calf muscles, because this can make all the difference," he said.

Consultant surgeon Alex Attard said there has not been a known case of DVT emanating from long-haul flights in Malta. However, he added, when the DVT is minor, this usually goes unnoticed, and the extent of the problem is not known.

A Welsh tenpin bowler collapsed and died from a suspected DVT last month, the day after he flew to Melbourne. According to the BBC, between 500 and 1,000 British airline travellers die of DVT annually. Between 8,000 and 9,000 Britons develop DVT every year.

Mr Attard, who specialises in general and vascular surgery, said most times DVT does not have any complications and there is no need for people to panic if they do get it.

"The majority of people recover," he said, adding that even pulmonary embolism is not necessary fatal. What is more common than pulmonary embolism is post-phlebitic lymph syndrome, which normally involves high blood pressure in the leg, swelling or pigmentation.

Asked about the initial symptoms of DVT, Mr Attard said some people suffer no symptoms at all. Sometimes there is swelling in the leg or pain in the calf.

Mr Attard recommends that people keep well hydrated, adding that the tendency is for people not to drink for long periods of time. Travellers are also urged not to remain sitting down for long hours but to move around. It is also important to engage the calf muscles when sitting down, he said, adding that below-the-knee compression socks go a long way to prevent risks.

Some people also opt for anticoagulant drugs, which may prevent the formation of new clots. Mr Attard said low-molecular-weight herparins are pre-packed and can be self-injected. Although he expressed his belief that this might be a little over the top, the injections have very little side effects. However, although they might be effective, it is still unknown whether they are actually required, he added.

Recommendations

Tonic, the bimonthly magazine of pharmaceutical company Sanofi-Aventis, recommends the following in-flight precautions.

¤ Drink one litre of water every five hours since humidity levels in aircraft cabins are often close to zero.

¤ Leave your seat every hour and walk around for a few minutes to stretch your legs.

¤ While seated rotate your ankles and contract calf muscles by pressing on the ball of each foot and raising the heel. Do not cross the legs.

¤ Limit alcohol, coffee and tea intake since these cause dehydration.

¤ Do not take sleeping pills since these can cause dangerous prolonged immobility in a sitting position.

¤ Wear loose-fitting clothing.

¤ For people with major risk factors - including certain cardiovascular diseases, history of thrombosis, coagulation disorders, pregnant women or those who gave birth within the past two months, cancer or those on hormone treatments - wearing support tights can be helpful.